Vibrating screen



Sept. 8, 1931.

C. G. A. SCHMIDT, JR

VIBRATING SCREEN Filed Sept. 21, 1929 WWA/5.53.'

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Patentedr Sept. 8, 1931 UNITED STATESl PATENT OFFICE CARL G. A. SCHMIDT, JR., 0F IKENNET'Iv SQUARE, PENNSYLVANIA, ASSIGNOR T0 AMERCAN ROAD MACHINERY COMPANY, OF KENNETT SQUARE, PENNSYLVANIA, A

CORPORATION OF DELAWARE VIBRATING SCREEN Application filed September 21, 1929.

This invention relates to a vibrating screen adapted for the classification of powdered or granular material and more parlticularly to a supporting means for such vibrating screen.

Vibrating screens of the type described generally mount rotating shafts having eccentric weights or the like arranged for imparting vibratory movement tothe screen.

U Such screens are supported in general by invention to provide supporting means for a ,A terial through a screen cloth. more, even this relatively low periodof visome resilient means such as springs adapted to permit the vibratory movement and absorb recoil. It is found, however, that when j springs are so used, there is an absenceA of jolting action and, while the frequency of vibration is of the order of 1800 times per minute, or the like, it is found that there is considerable trouble in getting fine ina- Furtherbration causes crystallization in the metallic supports or springs, whereby failure by fractures occurs.

It is accordingly the object of the present screen of this' character whereby a jolting action is effected without, however, the disadvantage of crystallization in the supporting means.

In the drawings:

Fig. 1 is a fragmentary transverse sectional view of the screen and the supporting means.

Fig. 2 is a fragmentary side elevation partly in section showing the supporting means.

Fig. 8 is a detail showing a pad or arm supporting the screen.

Fig. 4 shows a casing or housing embodied in the supporting means.

Serial No. 394,168.

2, there is mounted on the screen an eccentric vibrating device 6. While this type of device is disclosed, it will be clear that any equivalent vibrating means may be used.

An upright cylindrical casing 8 is mounted on the support 2 and isprovided with a cap 10, preferably threaded on the upper end thereof. The casing is provided with an upwardly extending slot 12. Viithin the casing are arranged a plurality of rubber balls '14 between which extends a pad or arm 16 carried by the screen, this arm eX- tending through slot 12. As shown in Fig. 2, the combined vertical extent of the two balls 14 and the pad 1G is such as to project the upper ball beyond the top of the casing. By this arrangement, adjustment of cap 10 serves to increase or decrease the normal tension on the balls, thereby regulat-ing both amplitude and period of the vibrations of the screen. As the screen is vibrated by means 6 at, say, 1800 times a minute, the vibratory motion is imparted to the rubber balls. By reason of the tension on these balls, each impact imparted thereto will produce a violent and extremely rapid up and down movement of pad 16 which movement will in turn be imparted to the screen. The result is a violent jolting aotion which serves very effectively to produce proper screening of the finest material.

lVhile rubber balls have been specified as the resilient supporting means, it is possible to substitute therefor cylinders or blocks of rubber which will serve the same purpose, so far as vibration is concerned. It is found most desirable to use balls, however, since during the vibration rotary movement takes place, whereby new surfaces are constantly being presented to the reaction of the adjacent portions of the casing and pad 16. Furthermore, rubber balls are common articles of commerce and are consequently inexpensive.

The balls, being made of rubber, are not subject to crystallization and furthermore, absorb the vibrations so that no crystalliza-- tion of the adj aoent metallic parts occurs.

Vhat I claim and desire to protect by Letters Patent is:

1. In combination, a vibrating screen, an arm carried by the screen, a support, and a plurality of rubber balls earrled by the support, the arln being interposed between the rubber balls.

2. Inweombinatonl, .a Vbratngfscreen, an arm carried by the screen, a supportLa plurality of rubber balls carried by the sup port,` the arm beng interposed between theurubber balls", andlneans fr adjustingy the normal degree of stress on the balls.

3. In cornblnatlon, a vlbratory sereelna support, a easing on the support;` rubber balls Wltlnn the easlng, meansafor achustmg.

the rubber balls, and an arm on the screen extending Within the easing and between the rubber balls.

4. In combination, a vbratngfscreen, an, arm .earrled by the screen7 a.. supportyancb a plurality of Vrubber balls earredrfby the support, the arm being interposed.betweenl the rubber ba1ls-, and, tbe balls being free to rotate relative toV the support.

5. InA combination,,avbratory screen,V aV

suppprt,` a casingY onxtbe support, rubber ball- Wtlinthe casing, means for adjust-,-

ing the rubber balls, and an. arm on the screen extendlngwvlthm tlre casing and between the rubber balls,.the balls belngv free lto rotate Within tlre easing.

Inetest-ilnonyy of Whielr invention, Ihave hereunto'set my hand, .at Kennett Square, Pa., on thisv 16th clay of Sept., 1929.

CARL G. A". SCHMIDT, JR. 

